1. Field of the Invention
The device and method as described herein relates to the processing of synthetic yarn and specifically to the processing of multifilament yarn by commingling the filaments by fluid impingement as the yarn moves along a directed path.
2. Description of the Prior Art and Objectives of the Invention
The processing of multifilament yarns such as polyester, polypropylene and other synthetic types is greatly enhanced when the filaments are sufficiently adhered so the yarn can be smoothly directed along guides, eyelets, rollers and other means, as for example when used in weaving, knitting or other procedures. The cohesion of multifilament yarns has been devised in the past by imparting a twist to the yarn. In recent years an alternative cohering method has been employed using air entanglement to provide cohesion without twisting the yarn filaments. Air entanglement or "commingling" the yarn induces filament intersections or nips which, if properly spaced, allow the yarn to be more easily handled during subsequent processing. If only a limited number of nips per meter, having low cohesion, is sufficient for a particular operation, such as 5-10 nips per meter, then air jets of conventional design can be employed at relatively high yarn speeds. U. S. Pat. No. 3,958,310 demonstrates one of many conventional methods for interlacing multifilament yarns using streams or jets of air.
If closely spaced and more durable nips are required, it has been necessary in the past to utilize entanglement processes which provide low tension to the yarn but at relatively low operating speeds. Such low speed processes can cause the yarn costs to escalate. A low tension, high speed air entanglement process has thus not been available prior to the invention described herein to provide the cohesion desired for modern high speed looms and other equipment.